Colin Andrew Sheffield, a name I normally associate with the Elevator Bath imprint (which he founded in 1998), brings his deft touch to an hour-long recording for Invisible Birds, a small label devoted to limited edition CDs and DVDs whose material is, not surprisingly, evocative of birds and the landscapes they inhabit. Such a concept at first might sound restrictive but the label's material not only includes bird song, twitters, chirps, calls, and wing flutter but environmental sounds associated with birds such as bells, water, sand, rain, snow, trees, and air. In other words, a given recording's range of potential sounds is actually huge.

As it turns out, Signatures, which Sheffield composed using a computer, turntable, sampler, and a portable 64-track digital workstation, only modestly features bird sounds as part of its sonic palette (despite being formally issued on Olivier Messiaen's 100th birthday) but it's a beautiful recording nonetheless (of course it's likely the case that said bird sounds are present but obscured). Those who prefer their ambient sound sculpting to be deep and immersive will find much to plunge into once “Beneath The Waves” appears with twenty minutes of oceanic ambient swirl. Faintly audible beneath the immense mass is an almost imperceptibly swaying rhythm reminiscent of an anchored ship's gentle rocking. Two shorter pieces occupy the recording's center. Bird sounds appear to be overtly heard during “Arise” in the sharp, scissors-like sounds that swell into a seething mass; the violence suggested by the six-minute piece's relentless churn calls to mind the music Bernard Hermann composed for Hitchcock's The Birds, specifically in those moments where the birds attack the schoolchildren and the townsfolk. The more blurrily-focused “Surrender” is at first as intense but gradually contracts into a semi-becalmed vaporous mass. One wouldn't expect twenty-eight minutes of fluttering organ tones and smears swimming in a sea of crackle and static to hold one's attention but “Breath Of Day” does exactly that when its elements advance and recede in constant transformation. That Sheffield's four pieces are such fully-realized exemplars of ambient sound sculpting helps make Signatures a stand-out release.